Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L83/00—Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon only; Compositions of derivatives of such polymers
  • C08L83/04—Polysiloxanes
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
  • C08G77/04—Polysiloxanes
  • C08G77/12—Polysiloxanes containing silicon bound to hydrogen
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
  • C08G77/04—Polysiloxanes
  • C08G77/14—Polysiloxanes containing silicon bound to oxygen-containing groups
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
  • C08G77/04—Polysiloxanes
  • C08G77/20—Polysiloxanes containing silicon bound to unsaturated aliphatic groups
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
  • C08G77/80—Siloxanes having aromatic substituents, e.g. phenyl side groups
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2205/00—Polymer mixtures characterised by other features
  • C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
  • C08L2666/28—Non-macromolecular organic substances

Definitions

• the general field of the invention is that of silicone elastomer compositions crosslinkable by addition and / or condensation.
• the polyorganosiloxanes considered (POS) are of the cold vulcanizable type (RTV), knowing that conventionally they are in the form of a two-component system (RTV-2), the vulcanization of which can be accelerated when hot.
• the present invention relates to adhesive silicone compositions which can be crosslinked by addition and also employing condensation reactions to develop adhesion.
• the invention also relates to the use as an adhesive of such a silicone composition.
• crosslinking and incident hardening of these silicone compositions participate in the adhesion mechanism which makes it possible to bond the two solids to one another.
• Crosslinking by addition involves unsaturated groups, in particular alkenyls and more particularly vinyls (Vi), linked to silicon in the POS (Si-Vi units) as well as hydrogens linked to silicon of the same or another POS ( SiH patterns). These reactions can be assimilated to hydrosilylations of the Si-Vi units with Si-H units.
• the crosslinking by addition can be advantageously catalyzed by metallic compounds which are, respectively, of the platinum type.
• silicone elastomeric compositions usable for coating different fibrous supports woven or not. After crosslinking, the film coated on the support forms a protective and mechanical reinforcement coating.
• Such fibrous supports thus coated with a crosslinked silicone elastomer film can be used for the manufacture of airbags for the personal protection of occupants of vehicles ("AIRBAG").
• An example of such silicone elastomer compositions is given by European patent application No. 0 681 014, in the name of the applicant and concerning a silicone elastomeric coating composition, of the type that can be cold vulcanized and consisting of the mixture formed of:
• adhesion promoter exclusively comprises:
• (IV.2) at least one organosilicon compound comprising at least one epoxy radical
• the silicone coating obtained after crosslinking of the coating film based on this composition has good properties of hardness, mechanical strength, surface uniformity, and heat resistance.
• the promoter IV according to the invention claimed in this European patent application provides an improvement in the adhesion of the coating to the fabric. This is reflected in a standard wrinkling test FFG 37 110 of a coated fabric, by a threshold ranging from 350 to 600 cycles for the samples tested in the examples.
• EP 0 326 712 discloses a crosslinkable POS composition comprising:
• an adhesion promoter comprising glymo GLYMO, and a diallyl ether of trimethyl-ol-propane, ethylene glycol or glycerol.
• a silicone composition can be used as an adhesive.
• the maximum adhesion values obtained are of the order of thirty kilos per cm 2 and vary according to the substrates. Faced with such a state of the art not offering an adhesive based on a silicone composition crosslinkable by addition / condensation and having all the specifications expected for the adhesives, namely:
• Another essential objective of the present invention is to provide a crosslinkable silicone composition or a use thereof for bonding electrical / electronic components or mechanical parts in particular in the automotive field or in the household appliance field ( connectors).
• Another essential objective of the present invention is to provide a process for bonding at least two substrates using a crosslinkable silicone composition, said process making it possible to easily and economically obtain a solid and durable assembly between the two substrates .
• the inventors had the merit of highlighting in a completely surprising and unexpected manner and after long and painstaking research, a judicious and advantageous selection of a subgroup of crosslinkable silicone elastomer compositions, among the large group of compositions disclosed in EP 681 014.
• This sub-group has the distinction of being singularly adherent and moreover having all the characteristics and in particular rheological and mechanical to form an excellent adhesive.
• an adhesive silicone composition crosslinkable of the type of those comprising: (I) at least one polyorganosiloxane having, per molecule, at least two alkenyl groups linked to silicon;
• VI optionally at least one crosslinking inhibitor, (V ⁇ I) and optionally at least one polyorg.anosilox.ane resin carrying siloxyl units Q and / or T and alkenyl groups, characterized by - ⁇ - its peel strength F. (N / mm) measured in a T test, greater than or equal to 0.25, preferably 0.50;
• hardness D after crosslinking, measured by a test T s (DIN 5335), greater than or equal to 35, preferably between 40 and 65 and even more preferably between 40 and 55 .
• crosslinkable adhesive silicone composition thus defined in accordance with the invention by its functional characteristics Fp, ⁇ , Rd, D corresponds to a limited number of formulations. These functional characteristics qualitatively and quantitatively determine the compounds I to VII of the composition. It is indeed entirely within the skills of a person skilled in the art to prepare the composition according to the invention, on the basis of the characteristics ⁇ , Fp, Rd, D, using the teaching of this presentation and his normal scientific and technical knowledge.
• composition according to the invention is a completely performant glue, in a liquid form easily applicable by any means known per se and suitable for the substrates to be assembled (eg calendering - casting - rollers - doctor blade ... ).
• This silicone adhesive composition has a high adhesion power as well as a stability in storage before crosslinking, a stability of the bonding after crosslinking and a resistance to the temperature of the bonding joint, which is entirely satisfactory.
• Concerning the characteristic ⁇ , the test Tp for measuring the peel force Fp, is defined by the following protocol:
• the mixing of components I to VII is carried out manually or using a pneumatic gun with static mixer.
• the adhesive silicone composition I to VII is deposited by screen printing with different grids (nylon grid of 75 microns or stainless steel grid of 50 microns). This makes it possible to vary the amounts of composition deposited from 20 to 100 g / cm 2 .
• test pieces are sheets of plastic substrate Sa as defined below in Example 4, which have dimensions of 100 ⁇ 150 mm.
• the coated surface is 50 x 100 mm.
• tissue test pieces are 150 x 100 x 2 mm are joined to each other and placed between two non-stick sheets. They are then subjected to a pressure of one tonne supplied by a hydraulic press of 10 tonnes, heated to 160 ° C.
• the pressure applied to the fabric is approximately 30 N / cm 2 (neglecting the thickness of the RTV composition bonding joint).
• the pressing time is 3 min after closing the press.
• the measurement of the coat is carried out with a dynamometer with 100 N cell.
• the draw is made on 50 mm of housing (coating width, removal of edge effect) and on a length of 50 mm, at 50 mm / min. 4 - Result
• the peeling force Fp is expressed in N / mm.
• viscosity ⁇ of the adhesive silicone composition according to the invention corresponds to a quantity of dynamic viscosity at 25 ° C called “Newtonian", that is to say the dynamic viscosity which is measured, in a manner known per se, at a sufficiently low shear speed gradient so that the viscosity measured is independent of the speed gradient.
• This viscosity ⁇ (characteristic ⁇ ) is that measured within 5 min following the mixing of all the constituents I to VII, before the hardening induced by the crosslinking by addition / condensation appears, which does not fail to occur. produce as soon as products I, II, III and possibly IV are brought into contact, and or as soon as products IV and I, II, III, VII, react with each other by condensation under the effect of ambient humidity and / or by opening epoxy rings.
• the viscometer can be used rheometer type needles such as those of Brookfield ® brand.
• the state of the composition after crosslinking is the state in which the composition must be in order for the Tp, Td and Ts tests to be carried out. It is defined by reaching a plateau value of its extension module and its hardness.
• the test Td for measuring the tear resistance Rd is that meeting the standard ASTM - 524A.
• the hardness D it is measured by the Ts test which corresponds to a DIN 5335 standard.
• the present invention also relates to the use as adhesive of the type that comprising: (I) at at least one polyorganosiloxane having, per molecule, at least two alkenyl groups linked to silicon;
• the composition used according to the invention is preferably that as defined above.
• the peeling force F p (N / mm) measured in a test T p is greater than or equal to 0.25, preferably to 0.50.
• composition I to VII used according to the invention has, in crosslinked form, the characteristics ⁇ , ⁇ , ⁇ as defined above. Thanks to the use recommended by the invention, an efficient and economical crosslinkable silicone adhesive is available.
• compositions and the use according to the invention are advantageous in that they provide a quick-setting hot glue (for example between 10 and 180 s at 160 ° C., depending on the case), said glue being stable. for several days at room temperature.
• a quick-setting hot glue for example between 10 and 180 s at 160 ° C., depending on the case
• said glue being stable. for several days at room temperature.
• the fact that it is very easy to handle when cold is another positive point which is particularly appreciable in practice.
• the composition and use of this RTV adhesive silicone allows non-fusible bonding. This means that once crosslinked, the composition according to the invention does not transform back into liquid since it is not thermoplastic.
• the heat resistance of a bonding according to the invention can for example reach 225 ° C.
• the alkoxylated organosilane (IV.l) of the promoter (IV) is more particularly selected from the products of the following general formula: (IV.l)
• R 1 , R 2 , R 3 are hydrogenated or hydrocarbon radicals which are identical or different from each other and preferably represent hydrogen, a linear or branched C 4 -C 4 alkyl or a phenyl optionally substituted by at least one C r C 3 alkyl,
• A is a linear or branched C 1 -C 4 alkylene
• - L is a valence bond or oxygen
• R 4 and R 5 are identical or different radicals and represent a linear or branched C 1 -C 4 alkyl
• - x 0 to 4, preferably 0 or 1 and more preferably still 0.
• vinyltrimethoxysilane is a particularly suitable compound (IV.l).
• the organosilicon compound (IV.2), is chosen
• R 6 is a linear or branched C 4 -C 4 alkyl radical.
• R 7 is a linear or branched alkyl radical.
• y is equal to 0, 1, 2 or 3, preferably to 0 or 1 and, more preferably still to 0,
• ⁇ E and D which are identical or different radicals chosen from linear or branched Cj-C 4 alkylene radicals, ⁇ z which is equal to 0 or 1,
• R 8 , R 9 , R 10 which are identical or different radicals representing hydrogen or a linear or branched C 4 -C 4 alkyl, hydrogen being more particularly preferred
• R 8 , R 9 , R 10 can alternately constitute together with the two carbons carrying the epoxy, an alkyl ring having 5 to 7 members,
• - G is a monovalent hydrocarbon group, free from any unfavorable action on the activity of the catalyst and preferably chosen from alkyl groups having from 1 to 8 carbon atoms included, advantageously, from the groups 11
• G has the same meaning as above and r has a value between 0 and 3, for example between 1 and 3.
• the compounds (IV.2) are therefore preferably epoxyalkoxysilicones and more preferably still epoxyalkoxymonosilanes (IV.2 a).
• the adhesion promoter (IV) is e.g.: vinyltrimethoxysilane (VTMS) / 3-glycidoxypropyltrimethoxysilane (GLYMO) / butyl titanate.
• this ratio is preferably between 2: 1 and 0.5: 1, the 1: 1 ratio being more particularly preferred.
• the adhesion promoter is present in an amount of 0.1 to 10, preferably 0.5 to 8 and more preferably still 1 to 5% by weight relative to all of the constituents of the composition.
• composition used according to the invention may comprise at least one unsaturated POS resin (VII) comprising at least two alkenyl residues, preferably vinyls per molecule.
• VI unsaturated POS resin
• the POS resin (VII) comprises in its structure from 0.1 to 20% by weight of alkenyl group (s), said structure having at least two different units chosen from units of types M, D, T and Q, at least one of these patterns being a pattern of type T or Q.
• this resin (VII) preferably corresponds to one of the following two formulas:
• the resin (VII) contains units Q at a rate of at least 5%, preferably at least 7%, and even more preferably at a rate of 8 to 30%.
• the resin (VII) comprises siloxy patterns T.
• the polyorganosiloxane (I) is by weight one of the essential constituents of the composition used according to the invention.
• it is a product having patterns of formula: a Z b Si0 4 . (a + b) (1.1)
• W is an alkenyl group, preferably vinyl or alkyl
• - Z is a monovalent hydrocarbon group, free from any adverse action on the activity of the catalyst and preferably chosen from alkyl groups having from 1 to 8 carbon atoms included, advantageously, from methyl, ethyl, propyl and 3,3,3-trifluoropropyl and also among the aryl groups and, advantageously, among the xylyl and tolyl and phenyl radicals, 13
• this polydiorganosiloxane it is advantageous for this polydiorganosiloxane to have a viscosity at least equal to 10 mPa.s, preferably to 1000 mPa.s and more preferably still between 5,000 and 200,000 mPa.s. Mention may be made, as example of compound (I), of polydimethylsiloxane.
• the polyorganosiloxane (I) can be formed only of units of formula (1.1) or can additionally contain units of formula (1.2). Likewise, it can have a linear, branched, cyclic or network structure. Its degree of polymerization is preferably between 2 and 5,000. Z is generally chosen from methyl, ethyl and phenyl radicals,
• siloxyl units of formula (1.1) are the vinyldimethylsiloxane unit, the vinylphenylmethylsiloxane unit and the vinylsiloxane unit.
• siloxyl units of formula (1.2) are the Si0 4/2 , dimethylsiloxane, methylphenylsiloxane, diphenylsiloxane, methylsiloxane and phenylsiloxane units.
• polyorganosiloxanes (I) are dimethylpolysiloxanes with dimethylvinylsilyl ends, methylvinyldimethylpolysiloxane copolymers with trimethylsilyl ends, methylvinyldimethylpolysiloxane copolymers with dimethylvinylsilyl ends, cyclic methylvinylpolysiloxanes.
• the polyorganosiloxane (II) is preferably of the type of those comprising siloxyl units of formula:
• - L is a monovalent hydrocarbon group, free from any unfavorable action on the activity of the catalyst and preferably chosen from alkyl groups having from 1 to 8 carbon atoms included and, advantageously, from methyl groups , ethyl, propyl and 3,3,3-trifluoropropyl and also among the aryl groups and, advantageously, among the xylyl and tolyl and phenyl radicals, - d is 1 or 2, e is 0, 1 or 2, d + ea a value between 1 and 3, 14
• polyorganosiloxane (II) examples include poly (dimethylsiloxane) (methylhydrogensiloxy) ⁇ , ⁇ dimethylhydrogensosiloxane.
• the polyorganosiloxane (II) can only be formed of units of formula (II.l) or additionally comprises units of formula (II.2).
• the polyorganosiloxane (II) can have a linear, branched, cyclic or network structure.
• the degree of polymerization is greater than or equal to 2. More generally, it is less than 5,000.
• Group L has the same meaning as group Z above.
• Examples of units of formula (11.1) are: H (CH 3 ) 2 Si0 1/2 , HCH 3 Si0 2/2 , H (C 6 H 5 ) Si0 2/2
• the ratio of the number of hydrogen atoms bound to silicon in the polyorganosiloxane (I) to the number of alkenyl unsaturated groups of the polyorganosiloxane (II) is between 0.4 and 10, preferably between 0.8 and 3.
• the polyorganosiloxane (I) and or the polyorganosiloxane (II) can be diluted in a non-toxic organic solvent compatible with silicones.
• the networked polyorganosiloxanes (I) and (II) are commonly called silicone resins.
• the bases of polyaddition silicone compositions may contain only linear polyorganosiloxanes (I) and (II) such as, for example, those described 15
• the catalysts (III) are also well known.
• the platinum and rhodium compounds are preferably used. It is possible, in particular, to use the complexes of platinum and of an organic product described in patents US-A-3,159,601, US-A-3,159,602, US-A-3,220,972 and European patents EP- A-0 057 459, EP-A-0 188 978 and EP-A-0 190 530, the complexes of platinum and vinylated organosiloxanes described in patents US-A-3,419,593, US-A-3,715,334 , US-A-3,377,432 and US-A-3,814,730.
• the generally preferred catalyst is platinum.
• the quantity by weight of catalyst (III), calculated by weight of platinum-metal is generally between 2 and 400 ppm, preferably between 5 and 200 ppm based on the total weight of the polyorganosiloxanes (I) and (II ).
• the charge (V) possibly provided is preferably mineral. It can be made up of products chosen from siliceous materials (or not).
• siliceous materials they can play the role of reinforcing or semi-reinforcing filler.
• the reinforcing siliceous fillers are chosen from colloidal silicas, combustion and precipitation silica powders or a mixture thereof. These powders have an average particle size generally less than 0.1 ⁇ m and a BET specific surface greater than 50 m 2 / g, preferably between 150 and 350 m 2 / g.
• Non-siliceous fillers such as diatomaceous earth or ground quartz can also be used.
• non-siliceous mineral materials they can act as a semi-reinforcing or tamping mineral filler.
• these non-siliceous fillers which can be used alone or as a mixture are carbon black, titanium dioxide, aluminum oxide, hydrated alumina, expanded vermiculite, unexpanded vermiculite, calcium carbonate, l zinc oxide, mica, talc, iron oxide, barium sulfate and slaked lime.
• These fillers have a particle size generally between 0.001 and 300 ⁇ m and a BET surface area of less than 100 m2 / g.
• the filler used is quartz or a mixture of quartz and silica.
• the load can be treated with all or part of at least one and / or the other of the compounds (IV.l) to (IV.3) of the promoter (IV). 16
• an amount of filler between 20 and 50, preferably between 25 and 35% by weight relative to all the constituents of the composition.
• the silicone elastomer composition comprises at least one retarder (VI) of the addition reaction (crosslinking inhibitor), chosen from the following compounds:
• polyorganosiloxanes advantageously cyclic and substituted with at least one alkenyl, tetramethylvinyltetrasiloxane being particularly preferred, - pyridine,
• acetylenic alcohols (Cf. FR-B-1 528 464 and FR-A-2 372 874), which are part of the preferred hydrosilylation reaction thermal blockers, have the formula:
• R is a linear or branched alkyl radical, or a phenyl radical;
• R ' is H or a linear or branched alkyl radical, or a phenyl radical; the radicals R, R 'and the carbon atom located at ⁇ of the triple bond possibly optionally forming a ring; the total number of carbon atoms contained in R and R 'being at least 5, preferably from 9 to 20.
• Said alcohols are preferably chosen from those having a boiling point above 250 ° C.
• Such a retarder (VI) is present at a rate of 3000 ppm at most, preferably at the rate of 100 to 2000 ppm relative to the total weight of the organopolysiloxanes (I) and (II).
• the silicone elastomer composition can be added with various conventional additives such as, for example, the dyes.
• the composition used according to the invention involves the constituents (I) to (VII) in the following proportions, in% by weight on a dry basis relative to the total mass: (I) 1 to 80 preferably 10 to 60 (II) 0.1 to 20 preferably 0.5 to 10
• the present invention relates to a bicomponent precursor system of the silicone elastomer composition described above.
• a precursor system is presented in two distinct parts A and B, intended to be mixed to form the composition, one of these parts A or B comprising the catalyst (III) and a single species (I) or (II) of polyorg-anosiloxane.
• this precursor system Another characteristic of this precursor system is, on the one hand, that its part A or B containing the compound (IV.l) of the promoter (IV) does not comprise the catalyst (III) and, on the other hand, that the resin (VII) can be used in part A or part B or in both parts A and B, part A or B containing the POS (II) and the resin (VII) being free of catalyst (III ).
• the compound (IV.3) is a butyl titanate, it is preferable that it is not contained in the same part A or B as the POS (II).
• composition can, for example, consist of a part A comprising the compounds (IV.l) and (IV.2) while the part B contains the compound (IV.3).
• a premix is first prepared by mixing a 18
• This premix serves as a base to obtain, on the one hand, a part A resulting from the mixture of the latter with the polyorganosiloxane (II) optionally a crosslinking inhibitor and finally the compounds (IV.l) and (IV.2) of the promoter (IV).
• Part B is produced by mixing a part of the premix referred to above and of polyorganosiloxane (I) as well as of coloring base, of catalyst (Pt) and of compounds (IV.3) of the promoter (IV).
• the unsaturated resin (VII) is used in dry form, without solvent external to the mixture (I) to (VII).
• the resin (VII) is incorporated into the POS silicone oil (I).
• the unsaturated resin (VII) is used in solution in an organic solvent, which can in practice be that used during manufacture.
• Removal of the solvent can be carried out before incorporating the resin into the premix or even after the latter has been produced.
• the first procedure is that which is preferred.
• Variants a and b of this first mode are indifferently implemented. It should be noted that in the case of variant b, it is preferred to remove the solvent at the end of the preparation of the premix.
• the viscosity of parts A and B and of their mixture can be adjusted by varying the amounts of the constituents and by choosing polyorganosiloxanes of different viscosity.
• parts A and B form a ready-to-use silicone elastomer composition (EVF II), which can be applied to the substrates to be bonded or coated by any suitable means (for example doctor blade or cylinder).
• EVF II silicone elastomer composition
• the crosslinking of the composition applied to the support to be coated can be caused thermally and / or by electromagnetic radiation (UV).
• UV electromagnetic radiation
• the substrates which can be bonded by the composition are made of thermoplastic or thermosetting polymer, preferably of phenoplast, of polyamide, 19
• polyester ABS, polycarbonate, PVC, polyether, polyolefin or epoxy resin.
• the substrates can also be metallic, it can be e.g.: raw or treated aluminum? raw or treated steels, or lacquered metals.
• the composition according to the invention is self-adhesive on aluminum (type AG3) and on steel (type Sollac R 1426) with a shear strength of 1 to 5 MPa and a 100% cohesive break in all cases.
• the field of application of the use recommended by the invention is advantageously that of the bonding of construction parts of vehicles, in particular automobiles, or that of the bonding of construction parts of household appliances, in particular washing machines. .
• bonding applications in the automotive industry can be:
• the present invention relates to a method of bonding at least two substrates S j and S 2 characterized in that it essentially consists:
• the glue or the adhesive composition according to the invention, the use of a silicone composition (I) to (VII) as an adhesive as well as the bonding method according to the invention provide extremely advantageous results in terms of strength. adhesion, stability to conservation before crosslinking or bonding stability, mechanical properties, resistance to bonding temperature, rheology before 20
• crosslinking suitable for the bonding application bonding capacity of substrates of various natures and cost price.
• premix No. 1 a suspension called premix No. 1 is prepared by mixing in a reactor at room temperature:
• premix No. 2 a suspension called premix No. 2 is prepared by mixing in a reactor at room temperature:
• VTMO vinyltrimethoxysilane
• GLYMO 3glycidoxypropyltrimethoxysilane
• the bicomponent is obtained by mixing at room temperature 100 parts of A and 100 parts of B. This gives composition C2.
• EXAMPLE 3 ALTERNATIVE TO THE PREPARATION OF THE PREMIX OF THE EXAMPLE
• the reactor is then placed under vacuum (15 mm Hg) and the temperature brought to 150 ° C. until elimination of the solvent.
• the adhesive performances (Bonding force Fp) of the two-component Cl C2 of Examples 1 and 2 are evaluated by a peel test Tp. For this, a layer of controlled thickness of the bicomponent is deposited between two substrates and crosslinking of the bicomponent is carried out.
• - Sa a polyamide 66 fabric of 235 dtex woven with 28 * 27 strands (i.e. 28 strands per cm in the warp and 27 strands per cm in the weft)
• - Sb a 140dtex PET polyester fabric woven with 28 * 27 strands (i.e. 28 strands per cm in the warp and 27 strands per cm in the weft)
• Bicomponent substrate 1 substrate 2 surface weight peeling force .g / m 2 N / mm
• Composition C2 also allows bonding to metal, in particular aluminum and plastics, in particular epoxy resins.
• this quick setting hot glue (10 to 180 seconds at 160 ° C. for example) is stable for several days at room temperature.
• composition C2 is adaptable to many applications such as the automotive and household appliance fields.
• composition C2 allows a non-fusible bonding which resists in particular up to 225 ° C. 24
• a 1 mm thick parallelepiped silicone seal is applied between two sterigmas.
• the test piece thus obtained after a crosslinking time in an enclosure at 150 ° C., is subjected to a tensile-shear stress.
• the bond is characterized by the constraint and the type of rupture (cohesive, adhesive ).
• an adhesion primer When using an adhesion primer: apply a light abrasive treatment to the covering surfaces to remove the surface oxide layer.
• Aluminum support allowing the preparation of test pieces with a Teflon part at the silicone seal to avoid adhesion of the elastomer on the support block.
• This template allows the production of a 1 mm thick joint with a bonding surface of 25 mm x 12.5 mm.
• test piece Prepare the sterigmas and the template under the conditions of paragraph C. h Provide three test pieces for each determination. C Place the lower sterigms and block them, d. Then by operating test piece by test piece: 25
• test specimens When the gluing of the test pieces is finished moderately block the clamps holding the upper sterigmas. f Place the test specimens to be crosslinked in a 150 ° C conditioned enclosure. g After crosslinking, unmold the test specimens. Continue the polymerization cycle under the conditions recommended for the product, keeping them in a horizontal position in the conditioned enclosure.
• the surface S is normally 312.5 mm 2 , the instructions for use of the dynamometer provides for the possibility of calculating the tensile strength from the corrected surface.
• the support plates are made of raw aluminum AG3, dimensions 100 x 25 x 4 mm. Composition C2 is placed between two of these plates so as to create a joint 1 mm thick which occupies an area of 25 x 25 mm. 26
• Consolidation of the assembly takes place by heating at 150 ° C for 2 hours.
• the adhesion is measured using a dynamometer; the resistance to rupture of the assembly is expressed in MPa and the rate of cohesive or adhesive rupture.
• the adhesion is measured on the one hand by a shear test (standard ASTM-624-A) and on the other hand by a 180 ° peel resistance test (standard NFT-46008).
• the steel used is that marketed under the name SOLLAC
• the step on a first strip of steel 500 microns thick, 150 mm long and 25 mm wide, is positioned at 90 ° with respect to the steel strip, two stainless steel spacers 50 ⁇ m thick and 10 mm wide. The first at one end of the steel strip, the second at a distance of 60 mm from the first.
• - 3rd step Stoving of the "sandwich” at 150 ° C for 1 minute.
• - 4th step Crosslinking of the silicone adhesive, under a heating press at 200 ° C for 2 minutes under 700 to 900 MPa pressure.
• Step 1 In a first strip of steel 500 microns thick, 150 mm long and 25 mm wide, is positioned at 90 ° with respect to the steel strip, two stainless steel spacers 50 ⁇ m thick and wide 27
• the first at one end of the steel strip, the second at a distance of 10 cm from the first.
• - 4th step Crosslinking of the silicone adhesive, under a heating press at 200 ° C for 2 minutes under 700 to 900 MPa pressure.
• - 5th step The parts free of adhesive are folded at 90 °, symmetrically. These two parts are then found in the extension of one another by forming an angle of 180 °. They will serve as grip points for the jaws of the dynamometer to assess adhesion by 180 ° peeling.
• the mean value of the breaking strength, R F / S where F is the tensile force in Newton of the movable jaw at the time of the break and S is the surface in mm 2 of the overlap between the two plates (or surface of the silicone glue in contact with a plate, i.e. 1500 mm 2 ), is equal to 2.3 Mpa.

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Adhesives Or Adhesive Processes (AREA)
• Compositions Of Macromolecular Compounds (AREA)

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• 1998
  • 1998-02-27 FR FR9802651A patent/FR2775481B1/fr not_active Expired - Fee Related
• 1999
  • 1999-02-24 IL IL13779799A patent/IL137797A0/xx unknown
  • 1999-02-24 EP EP99936084A patent/EP1058712B1/de not_active Expired - Lifetime
  • 1999-02-24 AU AU32558/99A patent/AU3255899A/en not_active Abandoned
  • 1999-02-24 WO PCT/FR1999/000419 patent/WO1999043753A1/fr not_active Ceased
  • 1999-02-24 AT AT99936084T patent/ATE385248T1/de not_active IP Right Cessation
  • 1999-02-24 TW TW088102746A patent/TW518359B/zh not_active IP Right Cessation
  • 1999-02-24 ES ES99936084T patent/ES2303382T3/es not_active Expired - Lifetime
  • 1999-02-24 TR TR2000/02472T patent/TR200002472T2/xx unknown
  • 1999-02-24 DE DE69938078T patent/DE69938078T2/de not_active Expired - Lifetime
  • 1999-02-24 US US09/623,083 patent/US6562180B1/en not_active Expired - Lifetime
  • 1999-02-24 CA CA002321884A patent/CA2321884C/fr not_active Expired - Fee Related
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  • 1999-02-24 BR BRPI9908407-4A patent/BR9908407B1/pt not_active IP Right Cessation
  • 1999-02-24 JP JP2000533496A patent/JP2002504612A/ja active Pending
  • 1999-02-24 SK SK1285-2000A patent/SK12852000A3/sk unknown
  • 1999-02-24 PL PL99342610A patent/PL342610A1/xx not_active Application Discontinuation
  • 1999-02-24 KR KR1020007009527A patent/KR20010041395A/ko not_active Withdrawn

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